Boston celebrates as second bomber caught

As the manhunt for the second Boston bombing suspect, Dzhokhar Tsarnaev, finally ended Friday evening, relieved residents lined the streets to cheer departing law enforcement officials.

The 19-year-old was found hiding in a trailer boat in the backyard of a home in Watertown, a Boston suburb, after he escaped a shootout that killed his brother Tamerlan Tsarnaev.

The home owner found Dzhokhar covered in blood, hiding in the boat. He surrendered after a gunfight with law enforcement officials, who quickly flooded the area.

“We’ve closed an important chapter in this tragedy,” said US President Barack Obama in a late-night address, adding that investigations would continue.

Facing the country are several questions, he said: “Why did young men who grew up and studied here, as part of our communities and our country, resort to such violence?”

Investigators will be hoping to get some answers from Dzhokhar, who is in a serious condition in a hospital.

The arrest ended a dramatic four days after two bombs exploded at the Boston marathon finish line, killing three people and wounding 180 in the first attack on the US mainland since the September 11, 2001 terror attacks.

The chase for the brothers began hours after the FBI released their pictures and a video on Thursday.

The brothers, both of Chechen origin, left their hideout after Monday's bombings. They then visited a convenience store, but contrary to earlier reports, they did not rob it; they just happened to be there when it was being robbed.

They came under the radar of law enforcement officials soon enough.

They shot and killed – execution style – Sean Collier, an MIT campus police officer in Cambridge, another town outside Boston, for reasons not clear yet.

The brothers then carjacked a Mercedes SUV, telling its occupants they were the Boston bombers, before dumping them at a gas station, unharmed.

Law enforcement finally cornered them in a Watertown residential neigbourhood. The brothers fought back with guns, a grenade and pipe bombs.

Around 200 rounds were fired in the exchange. Tamarlan got out of the vehicle and tried to rush the police officers with explosives strapped to his body.

Dzhokhar, who was now behind the wheel, hurled the vehicle in the direction of the law enforcement officials, running over his brother who had fallen to the ground after being shot.

He soon abandoned the vehicle and escaped into the darkness. Nothing would be heard from him for the next 17 or 18 hours as authorities locked down the neighbourhood.

Law enforcement officers combed the area street by street, home by home. But there were no signs of Dzhokhar. And then gun shots were heard again, as evening fell. Residents and police officers cheered and clapped when Dzhokhar was finally taken alive after a gunfight.